JP2000239525A - Flame-retardant resin composition and layer insulation adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject flame-retardant resin composition that has a high degree of flame retardancy in no use of halogen compound by using a sulfur-containing thermoplastic resin, a specific epoxy resin, a specific reaction product and an epoxy curing agent. SOLUTION: The objective flame retardant resin composition comprises (A) 30-90 wt.% of a sulfur-containing thermoplastic resin (for example, poly(ether sulfone), (B) 10-70 wt.% of a non-halogenated polyfunctional epoxy resin with an epoxy equivalent of <=500 (for example, a bisphenol-F type epoxy resin), (C) 0.3-8 wt.% of phosphorus content (namely the weight ratio of the phosphorus atoms in the composition) in the reaction product between (i) a phosphorus compound bearing one or more P-H bonds in one molecule (for example, 9,10- dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) and (ii) a compound bearing 2 or more epoxy groups in one molecule (for example, a cresol-novolak resin), and (D) an epoxy resin curing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent flame retardancy without using a halogen-based flame retardant, and an interlayer insulating adhesive for a multilayer printed wiring board using the same. .

[0002]

2. Description of the Related Art Thermosetting resins typified by epoxy resins are widely used in electric and electronic equipment parts due to their excellent properties, and are provided with flame retardancy to ensure fire safety. Often have. Conventionally, these resins have generally used a halogen-containing compound such as a brominated epoxy resin. Although these halogen-containing compounds have high flame retardancy, aromatic bromine compounds not only separate corrosive bromine and hydrogen bromide when thermally decomposed, but also have high toxicity when decomposed in the presence of oxygen. May form bromodibenzofuran and polydibromobenzooxin. In addition, disposal of aging waste materials containing bromine is difficult. For these reasons, various studies have been made on phosphorus compounds and nitrogen compounds as flame retardants instead of bromine-containing flame retardants.

[0003] The flame retardancy of a thermosetting resin can be realized by blending a phosphorus compound and a nitrogen compound. The mechanism is that the nitrogen compound promotes the decomposition of the phosphorus compound and the generation of polyphosphoric acid by thermal condensation, and the polyphosphoric acid forms a film on the surface of the thermosetting resin, which results in a heat insulating effect, an oxygen shielding effect, and as a result, It is to prevent combustion. Various phosphorus compounds have been studied as flame retardants, but in order to maintain the properties of the thermosetting resin, the phosphorus compound is incorporated into the resin skeleton by some kind of chemical reaction with the resin. It is desirable.

When incorporating a phosphorus compound into the epoxy resin skeleton, a phosphorus compound that reacts with the epoxy group may be used. Such a phosphorus compound, 9,10-dihydro-9-
Oxa-10-phosphaphenanthrene-10-oxide is useful as a flame retardant for use in making epoxy resins flame-retardant because they react with epoxy groups.

On the other hand, in the field of printed wiring boards,
Copper foils with interlayer insulating adhesives used for multilayer printed wiring boards by the press-type build-up method, which have been receiving attention in recent years, often use a bromine compound to achieve flame retardancy. Certain compounds may be generated.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in order to solve such a problem, and has been made. A flame-retardant resin composition having a high flame retardancy without using a halogen compound and a flame-retardant resin composition having the same The present invention relates to an interlayer insulating adhesive for a multilayer printed wiring board using the same.

[0007]

SUMMARY OF THE INVENTION The present invention relates to an interlayer insulating adhesive for a multilayer printed wiring board, comprising the following components as essential components. (A) sulfur-containing thermoplastic resin, (B) epoxy equivalent 50
0 or less non-halogenated polyfunctional epoxy resin, (c) a reaction product of a phosphorus compound having at least one PH bond in one molecule and a compound having at least two epoxy groups in the molecule, and D) Epoxy curing agent.

[0008] In the present invention, the sulfur-containing thermoplastic resin (a) reduces softening of the resin during press molding, maintains the thickness of the insulating layer after molding, and imparts flexibility to the composition. And for the purpose of increasing the heat resistance of the insulating resin, but also to improve the electrical characteristics. The component (a) includes polyphenylene sulfide, polysulfone, polyether sulfone, bisphenol S-type phenoxy resin and the like. The ratio of the sulfur-containing thermoplastic resin is 30 to 90% by weight based on the whole resin.
It is preferred that If the amount is less than 30% by weight, the melt viscosity does not increase during molding and the thickness is not sufficiently maintained during molding. Therefore, it is difficult to secure the thickness of the insulating layer after molding, and the smoothness of the outer layer circuit becomes poor. . on the other hand,
When the content is more than 90% by weight, the adhesive composition is hard and lacks elasticity, so that the ability to follow the circuit unevenness of the base material during molding and the adhesion are poor, which causes formation voids. Further, if the terminal of the sulfur-containing thermoplastic resin is modified with a hydroxyl group, a carboxyl group or an amino group, the reactivity with the epoxy resin becomes good, so that after the thermosetting, the sulfur-containing thermoplastic resin and the epoxy resin are used. While suppressing the phase separation of
In order to improve the heat resistance of the cured product, the above modification is desirably performed.

[0009] The component (a), a sulfur-containing thermoplastic resin alone, lacks adhesiveness, has insufficient adhesiveness after molding, and has a high viscosity when dissolved in a solvent to form a varnish of a predetermined concentration. Poor coatability and workability when coating copper foil etc. In order to improve such a defect, a non-halogenated polyfunctional epoxy resin having an epoxy equivalent of 500 or less, which is the component (b), is blended. The mixing ratio of this epoxy resin is 10 to 70% by weight of the whole resin. If it is less than 10% by weight, the above effects cannot be expected, and if it exceeds 70% by weight, the effect of the component (A) sulfur-containing thermoplastic resin cannot be expected. As the epoxy resin (b), there are bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, aminophenol type epoxy resin and the like. If a novolak-type epoxy resin or a resin containing a hetero atom such as sulfur or nitrogen is used to make the multi-layered printed wiring board flame-retardant, the flame retardation of the multilayer printed wiring board is more effectively performed.

In the component (c), the phosphorus compound having at least one P—H bond in one molecule includes 9,9.
10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, 6-methyl-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10
-Oxide, 2,6,8-tritertiarybutyl-9,
10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, 6,8-dicyclohexyl-
9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, 6-phenyl-9,10-
Examples thereof include, but are not limited to, dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, diethylphosphine oxide, and diphenylphosphine oxide. When used as a flame retardant, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, 6-phenyl-9,10 not substituted with an alkyl group susceptible to thermal decomposition.
-Dihydro-9-oxa-10-phosphaphenanthrene-10 oxide, diphenylphosphine oxide, and the like are preferable, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 is more preferred because of availability of raw materials.
Oxides and diphenylphosphine oxide are preferred.

In the component (C), the compound having at least two epoxy groups in the molecule includes bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin. Resins, naphthalene type epoxy resins, biphenyl type epoxy resins, N-glycidyl compounds from aromatic amines and heterocyclic nitrogen bases, such as N, N-diglycidyl dianiline, triglycidyl isocyanurate, etc. It is not limited to these. However, halogen-containing epoxies such as brominated bisphenol A type epoxy resin and brominated novolak epoxy resin are excluded, but chlorine contained in normal epoxy resin originating from epichlorohydrin is unavoidably mixed in the epoxy resin production process. Become. However, the amount is in the order of several hundred ppm in hydrolyzed chlorine at a level known to those skilled in the art.

The reaction between the phosphorus compound having at least one P—H bond in one molecule and the compound having at least two epoxy groups in the molecule to obtain the component (c) is carried out by a P—H group. The degree of progress can be confirmed by the quantification of. This reaction is carried out at an excess of epoxy groups, in the presence of a bulk or inert solvent, at a reaction temperature of 80 to 200 ° C., preferably 100 to 150 ° C. for 1 to 24 hours, preferably 3 to 12 hours. Or it is performed under normal pressure. When a solvent is used, benzene, toluene, xylene, etc., which can easily remove the solvent after completion of the reaction, are usefully used.

The mixing ratio of the non-halogenated polyfunctional epoxy resin having an epoxy equivalent of 500 or less as the component (b) and the epoxy curing agent as the component (d) is determined in consideration of the fact that the component (c) has an epoxy group. Is set. However, if any of the functional groups is excessive, the moisture resistance, the moldability, and the electrical properties of the cured product are deteriorated. The component (c) is preferably contained such that the phosphorus content (that is, the weight ratio of phosphorus atoms) in the resin composition is in the range of 0.3% by weight to 8% by weight. If the proportion is less than 0.3% by weight, the effect of flame retardancy is insufficient, and if it exceeds 8% by weight, heat resistance and moisture resistance are lowered, and moldability is adversely affected, which is not preferable.

As the epoxy curing agent (d), those generally used can be used in the present invention. For example, phenol novolaks, amine compounds, imidazole compounds, acid anhydrides and the like are particularly limited. is not. Further, an amine complex of boron trifluoride, dicyandiamide or a derivative thereof, and the like can be given. Further, epoxy adducts or microcapsules of these can be used.

As described above, the present invention relates to (a) a sulfur-containing thermoplastic resin, (b) a halogenated polyfunctional epoxy resin having an epoxy equivalent of 500 or less, and (c) at least one resin per molecule.
Reaction product of a phosphorus compound having two P—H bonds and a compound having at least two epoxy groups in one molecule, and (d) an epoxy curing agent as essential components.
The inorganic filler may be blended in an amount of 40% by weight or less based on the total amount of the above components. Inorganic fillers, for example, fused silica,
Crystalline silica, calcium carbonate, aluminum hydroxide,
Examples include alumina, magnesium hydroxide, clay, barium sulfate, mica, talc, white carbon, and E glass fine powder.

Further, a silane coupling agent such as epoxy silane or a titanate coupling agent for improving adhesion to a copper foil or an inner circuit board or improving moisture resistance, and an antifoaming agent for preventing voids. Addition is also possible. As the solvent, one that does not remain in the adhesive after the adhesive is applied to a copper foil or the like and dried must be selected. For example, acetone, methyl ethyl ketone, toluene, xylene, n-hexane, methanol, ethanol, methyl cellosolve, ethyl cellosolve, cyclohexanone, dimethylformamide and the like are used.

For the copper foil with an interlayer insulating adhesive, an adhesive varnish in which an adhesive component is dissolved in a predetermined solvent at a predetermined concentration is applied to the anchor surface of the copper foil, and then dried at 80 to 130 ° C. to bond. It is prepared so that no solvent remains in the agent.
The thickness of the adhesive layer is preferably from 15 to 120 μm. 1
If the thickness is less than 5 μm, the interlayer insulation may be insufficient. If the thickness is more than 120 μm, there is no problem with the interlayer insulation. However, it is not easy to apply and the thickness of the multilayer printed wiring board is reduced. Will not fit.

This insulating sheet with copper foil is laminated on the inner circuit board by ordinary vacuum pressing and cured, whereby a multilayer printed wiring board having an outer circuit can be easily formed.

[0019]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. First, a synthesis example of the organic phosphorus-containing compound as the component (c) will be described. Next, examples in which these organic phosphorus-containing compounds are blended to prepare an interlayer insulating adhesive for a multilayer printed wiring board will be described.

<Synthesis Example 1> 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 was placed in a four-necked flask equipped with a thermometer, a stirrer, and a condenser.
100 parts of oxide (HCA manufactured by Sanko Chemical Co., Ltd.) (hereinafter, the blending amounts are all parts by weight) and cresol novolak epoxy resin (epoxy equivalent: 179, Nippon Kayaku E
OCN-1020), 184.3 parts, and 130-13
The reaction was performed at 5 ° C. for 6 hours to obtain a product (a). Elemental analysis revealed a phosphorus content of 5.1%. The epoxy equivalent was 658.

<Synthesis Example 2> 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 was placed in a four-necked flask equipped with a thermometer, a stirrer, and a condenser.
100 parts of oxide (HCA manufactured by Sanko Chemical Co., Ltd.) and phenol novolak epoxy resin (epoxy equivalent: 165;
152.8 parts of Nippon Kayaku Co., Ltd. (EPPN501H) was added, and reacted at 130 to 135 ° C. for 3 hours to produce a product (b).
I got Elemental analysis revealed a phosphorus content of 5.7%.
The epoxy equivalent was 636.

<Example 1> 100 parts of a polyether sulfone modified with a hydroxyl group at the terminal (weight average molecular weight: 24000, 5003P manufactured by Sumitomo Chemical Co., Ltd.), bisphenol F type epoxy resin (epoxy equivalent: 175, manufactured by Dainippon Ink and Chemicals, Inc.) 40 parts of Epiclone 830-S) and 50 parts of the product (a) obtained in Synthesis Example 1 were stirred in a solvent.
5 parts of 2-methylimidazole as a curing agent and a titanate coupling agent (KR-4 manufactured by Ajinomoto Co., Inc.)
6B) An adhesive varnish was prepared by adding 0.2 parts by weight and 20 parts of barium sulfate.

The insulating resin varnish was applied to an anchor surface of a copper foil having a thickness of 18 μm by a comma coater so that the thickness after drying became 80 μm, and dried to obtain a copper foil with an adhesive.
Further, a glass epoxy double-sided copper-clad laminate having a base material thickness of 0.1 mm and a copper foil thickness of 35 μm was subjected to pattern processing to obtain an inner circuit board. After the surface of the copper foil is blackened, the copper foil with the adhesive is set on both sides thereof, and 1.6 m is set between the set laminates.
A stainless steel mirror plate having a thickness of m is sandwiched, and 15 sets are put in one stage, and the temperature is raised at 3 to 10 ° C./min and the pressure is 10 to 30 kg / cm
^2. Under a condition of a degree of vacuum of -760 to -730 mmHg, a multilayer press was heated and molded at a temperature of 150 ° C. for 15 minutes or more using a vacuum press to produce a multilayer printed wiring board.

<Example 2> Polysulfone (manufactured by Teijin Amoko Engineering Plastics Co., Ltd., Udel P)
-1700) 100 parts, bisphenol F type epoxy resin (epoxy equivalent: 175, manufactured by Dainippon Ink and Chemicals, Inc.)
Epicron 830) (40 parts) and 50 parts of the product (a) obtained in Synthesis Example 2 were stirred and dissolved in a solvent, and 5 parts of 2-methylimidazole was used as a curing agent, and a titanate coupling agent (Ajinomoto Co., Ltd.) KR-46B) and 0.2 part by weight of barium sulfate were added to prepare an adhesive varnish. The production of the multilayer printed wiring board was performed in the same manner as in Example 1.

<Comparative Example 1> Bisphenol A type phenoxy resin (manufactured by Toto Kasei Co., Ltd., phenothot YP-40A)
SM40) 100 parts by weight average molecular weight 30,000) and 40 parts of bisphenol F type epoxy resin (epoxy equivalent: 175, Epicron 830 manufactured by Dainippon Ink and Chemicals, Inc.)
50 parts of the product (a) obtained in Synthesis Example 1 was stirred and dissolved in a solvent, and 5 parts of 2-methylimidazole was used as a curing agent, and a titanate coupling agent (manufactured by Ajinomoto Co., Inc.)
KR-46B) 0.2 part by weight and 20 parts of barium sulfate were added to prepare an adhesive varnish. Hereinafter, the production of the multilayer printed wiring board was performed in the same manner as in Example 1.

Comparative Example 2 100 parts by weight of a polyether sulfone modified with a terminal hydroxyl group (weight average molecular weight: 24,000) and a bisphenol F type epoxy resin (epoxy equivalent: 17)
5. Epicron 830) 4, manufactured by Dainippon Ink and Chemicals, Inc.
And 0 parts with a solvent by stirring and dissolving.
An adhesive varnish was prepared by adding 3 parts of methyl imidazole, 0.2 part by weight of a titanate coupling agent (KR-46B, manufactured by Ajinomoto Co.) and 20 parts of barium sulfate. Hereinafter, the production of the multilayer printed wiring board was performed in the same manner as in Example 1.

The obtained multilayer printed wiring board was measured for flame retardancy, surface smoothness, heat resistance to moisture absorption and peel strength, and the results shown in Table 1 were obtained.

(Measurement method) Inner layer circuit board test piece: 150 μm pitch between lines, 1.0 mmφ clearance hole 1. Flame retardancy: According to JIS C6481 2. Surface smoothness: JIS B 0601 R (max) 1. Moisture absorption solder heat resistance Moisture absorption conditions: pressure cooker treatment, 125 ° C,
3 atmospheres, 30 minutes Test conditions: n = 5, all five test pieces are at 280 ° C, 1
A sample that did not swell for 20 seconds was marked as “○”. 4. Peel strength: according to JIS C 6486

Table 1 Flame retardancy Surface smoothness Hygroscopic solder heat resistance Peel strength Example 1 V-0 5 μm ○ 1.0 kg / cm Example 2 V-0 3 μm ○ 1.1 kg / cm Comparative example 1 V-1 5 μm ○ 1.5 kg / cm Comparative Example 2 Combustion 3 μm × (3/5) 1.2 kg / cm

[0030]

The flame retardant resin composition of the present invention has excellent flame retardancy without using a halogen compound.
The interlayer insulating adhesive for a multilayer printed wiring board using this flame-retardant resin composition is excellent not only in flame retardancy, but also in heat resistance, and also in electrical characteristics and moisture resistance. , And is non-halogen, so there is little generation of harmful substances in the environment.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08G 59/30 C08G 59/30 C08L 63/00 C08L 63/00 A 71/10 71/10 C09J 163/00 C09J 163/00 171/00 171/00 181/00 181/00 H05K 3/46 H05K 3/46 T // H05K 1/03 650 1/03 650 F term (reference) 4F100 AB17B AB33B AK53A AK53G AK54A AK54G AK55A AK55G AK57A AK57G AL05A AL05G BA01 BA02 BA10A BA10B CA02A GB43 JB20 JJ03 JJ07A JJ07G JL11A 4J002 CC033 CD20X CN01W CN03W CN06W FD13X GJ01 4J036 AA05 AF06 AF13 AF19 CC02 FB15 EC03 EC01 EC03 EC01 AF01 AA16 BB01 CC09 CC41 CC43 EE02 EE06 EE07 EE19 GG02 GG27 GG28 HH16

Claims (6)

[Claims] 1. A flame-retardant resin composition comprising the following components as essential components. (A) sulfur-containing thermoplastic resin, (B) epoxy equivalent 50
0 or less non-halogenated polyfunctional epoxy resin, (c) a reaction product of a phosphorus compound having at least one PH bond in one molecule and a compound having at least two epoxy groups in the molecule, and D) Epoxy curing agent. 2. The composition according to claim 1, wherein the component (a) is one or two selected from polyphenylene sulfide, polysulfone, polyether sulfone and bisphenol S phenoxy resin.
The flame-retardant resin composition according to claim 1, which is at least one kind. 3. The flame-retardant resin composition according to claim 1, wherein the component (b) is one or more selected from bisphenol-type epoxy resins, novolak-type epoxy resins, and aminophenol-type epoxy resins. object. 4. The component (c) wherein a phosphorus compound having at least one PH bond in one molecule is 9,10.
The flame-retardant resin composition according to claim 1, 2 or 3, which is -dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. 5. An interlayer insulating adhesive for a multilayer printed wiring board, comprising the flame-retardant resin composition according to claim 1. 6. A copper foil with an interlayer insulating adhesive for a multilayer printed wiring board, wherein the interlayer insulating adhesive according to claim 5 is coated on the copper foil.